Issue no. 1, 2009
Published: Jan 09, 2009 |
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 Artificial molecule evolves in the lab |
| US scientists learn how to levitate tiny objects |
| Coffee next in line as biofuel source |
| Breakthrough turn-on for hydrogen power |
| A low-energy water purifier |
| Controlling rotor speed smooths wind power supply |
| New tool enables powerful data analysis |
| Artificial butterfly flaps like a pro |
| Could your social networks spill your secrets? |
| Invention: Software research assistant |
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| Artificial molecule evolves in the lab |
A new molecule that performs the essential function of life -
self-replication - could shed light on the origin of all living things.
The laboratory-born ribonucleic acid (RNA) strand also evolves in a test
tube to double itself ever more swiftly.
Rather than start with RNA enzymes - ribozymes - present in other
organisms, the team created its own molecule from scratch, called R3C.
It performed a single function: stitching two shorter RNA molecules
together to create a clone of itself. Further tinkering made this
molecule better at copying itself, but eventually clogged up in shapes
that could no longer sew RNA pieces together. To improve R3C, the
researchers redesigned the molecule to forge a sister RNA that could
itself join two other pieces of RNA into a functioning ribozyme. That
way, each molecule makes a copy of its sister, a process called cross
replication. The population of two doubles and doubles until there are
no more starting bits of RNA left.
The researchers sought to evolve their molecule by natural selection.
They did this by mutating sequences of the RNA building blocks, so that
288 possible ribozymes could be built by mixing and matching different
pairs of shorter RNAs. What came out bore an eerie resemblance to
Darwin's theory of survival of the fittest: a few sequences proved
winners, most losers. The victors emerged because they could replicate
fastest while surrounded by competition. |
| New Scientist / Science
Jan 08, 2009 |
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| US scientists learn how to levitate tiny objects |
Scientists at Harvard University in Massachusetts have found a way to
levitate the very smallest objects using the strange forces of quantum
mechanics, and might use it to help make tiny nanotechnology machines.
The researchers have detected and measured a force that comes into play
at the molecular level using certain combinations of molecules that
repel one another. The repulsion can be used to hold molecules aloft, in
essence levitating them, creating virtually friction-free parts for tiny
devices. Detection of this force opens the possibility of a whole new
class of tiny gadgets, according to the scientists.
The discovery involves quantum mechanics, the principles that govern
nature's smallest particles. By altering and combining molecules, tiny
machines could be devised which could have applications in surgery,
manufacturing food and fuel and boosting computer speed. |
| Reuters / Nature
Jan 07, 2009 |
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| Coffee next in line as biofuel source |
Coffee grounds - currently wasted or used as garden compost - could
become a cheap and environmentally friendly source of biodiesel and fuel
pellets. Spent coffee grounds contain 11-20 per cent oil, depending on
their type. This is competitive with other major biodiesel feedstocks
such as rapeseed oil (37-50$), palm oil (20$), and soybean oil (20%).
Scientists at the University of Nevada, Reno, used an inexpensive
process to extract oil from the coffee leftovers from a multinational
coffeehouse chain. This oil was then converted into biodiesel, which
could be used to fuel cars and trucks.
The world's coffee production is more than 7.2 million tonnes per year,
according to US Department of Agriculture figures cited in the study.
This could yield about 340 million gallons of biodiesel, say the
researchers. The process would be ideal for countries where coffee is
produced. A lot of defective coffee beans are discarded into the
landfills every year. Processing these beans as well as coffee grounds
would be an economical approach, according to the researchers. |
| SciDev.net / Journal of Agricultural and Food Chemistry
Dec 31, 2008 |
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| Breakthrough turn-on for hydrogen power |
Producing hydrogen from biofuels has been dogged by difficulties and
usually hydrogen is created using natural gas in fossil fuels, which
produces large amounts of CO2. Now scientists from the University of
Aberdeen say they have achieved a leap forward in the process.
Using a catalyst, the researchers have converted ethanol fermented from
biofuels into hydrogen. Although this has been done before, it has never
been effective and produced waste products such as poisonous carbon
monoxide. The catalyst used by the researchers is made from the rare
metals rhodium and palladium. Although these are expensive, only very
small quantities are needed. However, the disadvantage to the process is
that it requires temperatures of about 500C in order to work.
The process starts with fermentation. Crops are fermented using yeast,
producing ethanol and water. Then the catalyst is added to the mix of
ethanol and water, at temperatures of about 500C, which converts it into
hydrogen and carbon dioxide. |
| The Scotsman / ChemSusChem
Jan 07, 2009 |
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| A low-energy water purifier |
Access to clean water is severely limited in many parts of the world,
and while desalination plants can separate freshwater from sea and
brackish water, they typically require large amounts of electricity or
heat to do so. This has prevented desalination from being economically
viable in many poorer cities and countries. Oasys, a Yale University
spinoff, is driving one effort to change all this. Its researchers have
developed a novel desalination device that reduces the energy needed to
purify water to one-tenth of that required by conventional systems.
The most common approach to desalination is reverse osmosis, which
involves forcing a solution through a semipermeable membrane using
hydraulic pressure or thermal evaporation. The energy required to do
this has spawned new thinking on lower-energy technologies. Oasys is
using what it calls engineered osmosis. It establishes an osmotic
pressure gradient instead of using pressure or heat to force water
through a purifying membrane. The approach exploits the fact that water
naturally flows from a dilute region to one that is more concentrated
when the two solutions are separated by a semipermeable material,
thereby saving the energy normally needed to drive the process.
In Oasys's system, a 'draw solution' is added on one side of the
membrane to extract clean water from dirty water. The solution used by
Oasys is designed to have a high osmotic pressure and be easy to remove
through heating. |
| Technology Review
Jan 08, 2009 |
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| Controlling rotor speed smooths wind power supply |
A way to make wind power smoother and more efficient that exploits the
inertia of a wind turbine rotor could help solve the problem of wind
speed variation, according to new research. Wind is intermittent so the
power output of wind farms can be variable. Proposed measures to smooth
these fluctuations usually involve the installation of batteries or
capacitors to store electricity on good days and release their energy on
still days or when wind speeds are too high for system stability.
Now, researchers at the University of Wisconsin-Milwaukee have come up
with a different solution. They have devised a novel control method that
can mitigate power fluctuations using the inertia of the wind turbine's
rotor as an energy storage component. Simply put, they have created a
braking control algorithm that adjusts the rotor speed so that when
incoming wind power is greater than the average power, the rotor is
allowed to speed up so that it can store the excess energy as kinetic
energy rather than generating electricity. This energy is then released
when the wind power falls below average.
This approach, the team explains, precludes the need for external energy
storage facilities such as capacitors and the additional infrastructure
and engineering they entail. Their method also captures wind energy more
effectively and so improves the overall efficiency of wind farming
potentially reducing the number of turbines required at any given site. |
| Eurekalert.org / International Journal of Power Electronics
Jan 07, 2009 |
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| New tool enables powerful data analysis |
A powerful computing tool that allows scientists to extract features and
patterns from enormously large and complex sets of raw data has been
developed by scientists at University of California, Davis, and Lawrence
Livermore National Laboratory. The algorithm is compact enough to run on
computers with as little as two gigabytes of memory.
As the size of data sets has burgeoned, hand-in-hand with computer
capacity, analysis has grown increasingly difficult. A mathematical tool
to extract and visualize useful features from data sets has existed for
nearly 40 years - in theory. Called the Morse-Smale complex, it
partitions sets by similarity of features and encodes them into
mathematical terms. But working with the Morse-Smale complex is not
easy.
The new algorithm divides data sets into parcels of cells, then analyses
each parcel separately using the Morse-Smale complex. Results of those
computations are then merged together. As new parcels are created from
merged parcels, they are analysed and merged yet again. At each step,
data that do not need to be stored in memory are discarded, drastically
reducing the computing power required to run the calculations. |
| Eureka Alert / IEEE Transactions on Visualization and Computer Graphics
Jan 08, 2009 |
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| Artificial butterfly flaps like a pro |
Flying insects continue to inspire roboticists. Early in 2008, US
researchers added an artificial control system to the brain of moths,
effectively creating remote controlled cyborg insects. Meanwhile, others
are busy creating winged robots that flap around like real insects.
A few months ago, Dutch researchers designed a robotic dragonfly with a
wingspan of just 10 centimetres. And now there's a robotic butterfly to
add to the collection, courtesy of the Shimoyama-Matsumoto Laboratory at
the University of Tokyo. The 'butterfly' is simply a rubber band-powered
ornithopter, with wings created from a polymer membrane and supported by
plastic veins. But it does a remarkably good impression of a butterfly
once it's in the air. Its simple design would make a great DIY kit.
The study helped the researchers work out the best design for flying in
a forwards direction, and their robot has clearly mastered the art. It
still seems to only lose rather than gain altitude, but presumably
further study will crack that problem. |
| New Scientist
Jan 05, 2009 |
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| Could your social networks spill your secrets? |
Data-mining techniques are being used by marketeers and security
services to extract sometimes private information by assembling huge
amounts of data from web visits, emails, purchases, and more. Now
researchers at Google caution that by becoming entangled in ever more
social networks online, people are building up their own piles of
revealing data. And as more websites gain social features, even the
things users strive to keep private won't necessarily stay that way.
As a hypothetical example, combining public information on, say, the
business social network LinkedIn with that on another like MySpace could
reveal that one of your key business contacts spends their free time in
full Kiss makeup, even their two profiles are kept relatively anonymous
and are not linked directly in any way. That approach is dubbed 'merging
social graphs' by the researchers. In fact, it has already been used to
identify some users of the DVD rental site Netflix, from a supposedly
anonymised dataset released by the company. The identities were revealed
by combining the Netflix data with user activity on movie site IMDb.
The Google team's proposed solution is a kind of privacy warning system.
When you sign up for a new online service, it would take a look on the
internet and let you know if there's a risk that the new information you
are uploading could be used to make connections about you. |
| New Scientist
Jan 07, 2009 |
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| Invention: Software research assistant |
Having to become quickly knowledgeable about something you know little
about is a problem many people will be familiar with. Now Ari Rappaport
at the Hebrew University of Jerusalem thinks he has a solution.
He has written a computer program that analyses a section of text and
then searches the internet for relevant background information from
dictionaries, maps, encyclopaedias and video and image databases.
It then creates an annotated version of the text, stuffed with links to
the background material. This should dramatically improve a reader's
ability to understand the text, Rappaport says. |
| New Scientist
Jan 02, 2009 |
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